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排序方式: 共有6953条查询结果,搜索用时 15 毫秒
991.
Elizabeth P. Rice 《American journal of public health》1962,52(9):1605-1606
992.
Elizabeth P. Rice 《American journal of public health》1962,52(5):877-878
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995.
G Murialdo S Fonzi P Costelli GP Solinas C Parodi S Marabini M Fanciullacci A Polleri 《Cephalalgia : an international journal of headache》1994,14(3):205-209
Nocturnal urinary melatonin excretion was significantly decreased throughout an ovarian cycle in 12 migraine without aura patients compared to 8 healthy controls. Normal increases in urinary melatonin excretion during the luteal phase was less pronounced in the migraine patients. Melatonin excretion was further decreased during headache. The data indicate impaired pineal function in migraine. 相似文献
996.
C. D. Rice M. M. Banes T. C. Ardelt 《Archives of environmental contamination and toxicology》1995,28(4):464-470
Tributyltin (TBT) is a trialkylated organotin formulated for use primarily as a biocide for aquatic and agricultural industries. Although macrophages isolated from toadfish (Opsanus tau) are sensitive to exposure, very little is known about the effects of TBT on fish humoral immunity and non-specific cytotoxic cell (NCC) functions. To evaluate the effects of TBT on these parameters, channel catfish (Ictalurus punctatus) were given a single intraperitoneal injection of corn oil with 0 (vehicle control) or with 0.01, 0.1, and 1.0 mgTBT/kg as TBTCl. Three and seven days later, NCC activity and phagocyte oxidative burst were evaluated and related to allometric indices and hematology. The humoral immune response to Edwardsiella ictaluri was evaluated fourteen days after treatment. Peripheral blood neutrophilia and specific antibody secreting cell (SASC) numbers were the most sensitive parameters and were affected in all three TBT treatment groups. Allometric indices, peripheral blood lymphocyte and monocyte percentages, NCC activity, and phagocyte oxidative burst were less sensitive and were affected only at the highest dose of TBT. 相似文献
997.
A A Reid C H Kim A Thurkauf J A Monn B de Costa A E Jacobson K C Rice W D Bowen R B Rothman 《Neuropharmacology》1990,29(11):1047-1053
Several putative affinity ligands, based on the structures of phencyclidine etoxadrol, 5-methyl-10,11-dihydro-5H-dibenzo[a,d] cycloheptene-5,10-imine (MK801) and 1,3-di-(2-methylphenyl)guanidine (DTG) were evaluated in vitro for their ability to produce a wash-resistant inhibition of phencyclidine and sigma receptor sites in homogenates of the brain of the guinea pig. All the phencyclidine-based ligands, including 1-[1-(3-isothiocyanatophenyl)cyclohexyl]piperidine (Metaphit) and (+/-)-N-(2-isothiocyanatoethyl) MK801 [(+/-)-MK801-NCS], produced a wash-resistant inhibition of binding sites for phencyclidine, labelled by [3H]-1-[1-(2-thienyl)cyclohexyl]piperidine ([3H]TCP) and sigma binding sites, labelled by [3H]DTG. The DTG-based ligands, 1-(4-isothiocyanato-2-methylphenyl)-3-(2-methylphenyl)guanidine (DIGIT) and 1-(4-[2-(2-isothiocyanatoethoxy)ethoxy]-2-methyl-phenyl)-3-(2- methylphenyl)guanidine (DIGIE), produced a wash-resistant inhibition of sigma sites, at concentrations as small as 1 microM and also inhibited binding sites for phencyclidine at larger concentrations (100 microM). Both 1-(3-isothiocyanatophenyl)-1-ethyl-4-(2-piperidyl)-1,3-dioxolane (ETOX-NCS) and 1-[1-(3-bromoacetyloxyphenyl)cyclohexyl]-1,2,3,6-tetrahydropyri din e (Bromoacetyl-PCP) were the most potent and selective inhibitors of the binding of [3H]TCP, while DIGIT was the most selective inhibitor of the binding of [3H]DTG. Future studies will examine the selectivity of these agents in vivo after intracerebroventricular administration. 相似文献
998.
Short-term regulation of insulin-mediated glucose utilization in four-day fasted human volunteers: role of amino acid availability 总被引:1,自引:1,他引:0
Summary Glucose homeostasis in men fasted for 84 h was assessed using isotopes, indirect calorimetry and forearm balance techniques during a basal period and three sequential hyperinsulinaemic euglycaemic clamps each lasting for 150 min. Two protocols (n=12 in each) were used: subjects were either allowed to develop hypoaminoacidaemia or received a commercial solution of L-amino acids while maintaining near-basal plasma leucine levels. Insulin infusions resulted in 3-, 35- and 650-fold increases in plasma insulin levels in both protocols. The infusion of amino acids produced a rightward shift in the dose-response curve of insulin's effect on suppressing hepatic glucose production, indicating decreased sensitivity in addition to blunting of the maximal responsiveness. Total body glucose rate of disappearance was progressively increased with escalating insulin doses, but was 22% lower at the intermediate and highest insulin doses in the group that was infused with amino acids (3.44±0.53 vs 4.82±0.71 and 7.72±1.01 vs 10.36±1.08 mg·kg–1·min–1, respectively; p<0.05). Forearm balance data confirmed the isotopic data, since amino acid infusions blunted the insulin-mediated increase in net forearm glucose utilization (by 50–83%). Furthermore, the infusion of amino acids resulted in marked reductions in the rate of carbohydrate oxidation and storage as assessed by indirect calorimetry. The data indicate that the amino acid-mediated suppression of glucose utilization and carbohydrate oxidation is exerted on the responsive component of insulin action. 相似文献
999.
Use of disposable skin staplers for bowel anastomosis to reduce laparotomy time in war. 总被引:1,自引:0,他引:1 下载免费PDF全文
A. P. Wetherall G. J. Cooper J. M. Ryan D. E. Taylor G. P. Howell P. Rice 《Annals of the Royal College of Surgeons of England》1992,74(3):200-204
Laparotomy for penetrating wounds to the abdomen is demanding in terms of time, skill and resources. Any modification of existing techniques that will lessen these demands will be of benefit at surgery in forward areas in war. A previous paper (1) compared a method of small bowel anastomosis using disposable skin staplers with a two-layer handsewn anastomosis using fresh pig ileum. The stapled method was both significantly faster to perform and mechanically superior. In two further studies on a total of 12 pigs the stapled method has been compared with a single-layer and a double-layer handsewn small bowel anastomosis. All 12 pigs recovered from laparotomy without complication. Construction times were recorded. The quality of healing of the anastomoses was assessed by clinical observation, post-mortem and histological examination, and tensiometry. The skill required to perform the stapled anastomoses was estimated subjectively. The stapled technique was consistently faster than the handsewn methods. A Kolmogorov two-sample test showed an improvement in times when comparing the stapled method with the single layer, with a significance of P = 0.05. An improvement was also seen when the stapled method was compared with the double layer, with a significance of P = 0.01. There was no statistically significant difference between the construction times for the two handsewn methods. There was no evidence of anastomotic failure or haematoma at post-mortem and no adverse reaction to the metal staples. No features were identified on histology to indicate impaired healing with the stapled method. Tensiometry of the anastomoses showed that the stapled anastomosis is as mechanically reliable as the handsewn anastomosis.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
1000.